1. Field of the Invention
The invention relates to a filler body with a cross channel structure for a packing column or a static mixer apparatus, to a column with a filler body of this kind as a packing and to a mixer apparatus with a filler body of this kind as a static mixer structure.
2. Description of the Prior Art
A mixer apparatus for fluids is known from CH-A 547 120 in which the static mixer elements are built into a tube. An installation element of this kind consists of mutually contacting layers which form a cross channel structure with partly open flow channels. A packing body for columns is known from DE-A 26 01 890 which likewise has a cross channel structure. A material and/or heat exchange can be carried out with a column packing of this kind and indeed between a) a medium on surfaces of the packing, in particular a ripple film and/or a catalytically active coating, and b) a gas flow which flows through the channels formed by the packing surfaces.
If the fluid flows through the mutually openly crossing channels, then an interaction between the fluids in which a momentum exchange takes place results at the boundary surfaces between adjacent layers. As a result of this momentum exchange, turbulences arise in the channels in each case in the form of a turbulence braid (translational fluid flow with superimposed rotation), the turbulence nucleus of which extends in the channel direction. These turbulence braids induce further secondary turbulences. The driving forces of the turbulence braids, which are given by the momentum transfer, set in in such a manner that the turbulences remain upheld in the stationary state against the action of frictional forces. The turbulences further a mixing through of the fluid, on the one hand through a material exchange between adjacent channels, and on the other hand through a material exchange between boundary layers and inner spaces of the channels. Since the channels are inclined, the fluid is homogenized with respect to temperature and concentrations over the cross-section of the filler body, this however merely in the direction of the layers. The homogenizing and mixing effects are bought at the price of an energy dissipation which becomes noticeable as an additional flow resistance (or pressure drop).
The object of the invention is therefore to create a filler body with a cross channel structure for which the desired homogenizing and mixing effects set in at a reduced energy dissipation. The flow resistance in the filler body to be created should be lower in comparison with the conditions in known filler bodies with a cross channel structure, with however the separation performance of a material exchange column or the mixing action of a static mixer respectively largely remaining equally good.
The filler body with a cross channel structure is provided for a packing column or a static mixer apparatus. It is built up of mutually bordering layers in which in each case channels are arranged parallel to one another. At boundary surfaces between adjacent layers there extend lateral channels which are open to one another. These lateral channels form a cross-wise arrangement. At least a portion of the layers contain in each case central channels in addition to the lateral channels. A material separation at the boundaries between the central and the lateral channels is produced in about one-half of the cases with regularly arranged wall sections; in the zones of the other half the channel boundaries are open.
The layers of the filler body in accordance with the invention additionally comprise, besides lateral channels, central channels which are only partly separated from the lateral channels by walls. The lateral channels correspond to the channels of the known cross channel structure in which the parallel channels of the same layer are in each case separated over their entire length by walls. In the lateral channelsxe2x80x94as already in the known cross channel structurexe2x80x94primary turbulence braids are driven by the said interaction between adjacent layers. These primary turbulence braids induce secondary turbulence braids in the central channels. Thanks to the central channels a mixing action is achieved in a larger volume with an energy dissipation which is largely equally great. Since the individual layers xe2x80x94in contrast to the known cross channel structurexe2x80x94have a large permeability between the lateral channels of both sides, there results an additional homogenizing, which takes place perpendicular to the direction of the layers.